Last week’s zero-target, zero-catch performance against the Seahawks followed a similarly silent game in which Davis had two catches for 13 yards in the first 58 minutes of a 26-3 loss to the Giants.

The two-game totals: five targets, three catches, 37 yards and two defenses devoted to stopping San Francisco’s most formidable pass-catching threat.

On Friday, offensive coordinator Greg Roman said three teams in particular have designed take-away-that-tight-end game plans this season. Besides the Giants and Seahawks, the third team is presumably the Jets, who limited Davis to two catches for 28 yards in a 34-0 loss to the 49ers on Sept. 30.

“They come into the game saying, ‘Hey, Vernon Davis will not beat us,’ and they’ve done that,” Roman said. “Now the onus goes onto the other players. We’re very cognizant of it. … Some teams have taken drastic measures to make sure Vernon doesn’t get after them down the field or across the field.”

Davis, whose streak of 58 straight games with a reception was snapped last week, said the Giants and Seahawks have thrown similar coverages his way featuring two defenders.

“Nothing’s there,” Davis said. “When I run my corner routes, the cornerback is dropping to the corner. They are just taking stuff away, some of my explosive routes and stuff.”

Davis’ numbers have clearly attracted a crowd.

Prior to his recent two-game disappearance, he had 38 catches for 713 yards and eight touchdowns in his past eight games, a stretch that included last season’s playoffs. During his eight-game streak, he had four 100-yard performances, two fewer than he had in the first 87 games of his career.

Asked last week what could be done to counter game plans designed to stop him, Davis shrugged.

“That’s up to the offensive coordinator,” he said. “I don’t know what to do. I run my routes hard to get open, but there’s nothing there.”

For his part, Roman said the answer isn’t to force balls into a “triple-covered” Davis, but to make defenses pay for their undue attention to the tight end.

With a linebacker or safety – or both – occupied with Davis, the 49ers have run the ball effectively in the aforementioned games against the Seahawks, Giants and Jets. In those contests, they’ve averaged 167.3 rushing yards and 6.0 yards a carry.

“When people try to take away something to go to extreme measures,” Roman said, “I think you want to go do something else.”

Briefly: Left tackle Joe Staley returned to practice after he missed Thursday’s session with an illness. Staley was limited in practice. … Frank Gore (bruised ribs) was a full participant in practice for the second straight day.